Recumbent Exercise Apparatus

The present invention relates to an exercise apparatus. More particularly, the present invention relates to a recumbent exercise apparatus that allows a user to perform leg exercises in a seated position.

In the category of indoor aerobic exercise equipment, stationary bikes stand out as equipment that allows users to perform leg exercises in a seated position. Among them, the more commonly upright bikes and spinning bikes involve body postures and leg movement similar to riding a regular bicycle or road bike. In other words, while sitting on a seat, the upper body upright or leaning forward, both hands gripping the fixed handlebar in front of the seat, and both feet rotating the pedal crank assembly beneath the seat, achieving the effect of exercising the legs and aerobic exercise. However, the aforementioned body posture and leg movement may be somewhat challenging and unsafe for individuals with lower physical fitness levels, such as the elderly and those in middle to old age.

The recumbent bike is a relatively gentle form of stationary bikes, as shown in. Its pedal crank assembly (represented by only two pedalsin the figure) is located in the front and below the seat. Correspondingly, there is a backrestlocated behind and above the seatto provide the user with support to lean against, allowing the user to perform leg exercises by pedaling in a more relaxed and comfortable posture. This is particularly suitable for individuals with lower exercise capacity, such as the elderly and those in middle to old age, or individuals looking for mild exercise. During exercise, each pedalrotates along a predetermined circular path T. The diameter of the circular path is approximately 33 centimeters. If it's too small, it won't provide enough foot movement range and leg activity, and if it's too large, it may exceed the natural range of motion and become uncomfortable. In addition to rotating around the center of the circular path T, each pedalcan also freely rotate around its own axis corresponding to a lateral direction, allowing the foot angle to adapt to the constantly changing foot position during the user's rotation. In the typical usage, the seatis adjusted to an appropriate position so that when the pedalrotates to the farthest position from the seat(near the location of the right pedal in the figure), the user's legs are almost fully extended. Conversely, when the pedalrotates to the nearest position to the seat(near the location of the left pedal in the figure), the user's legs exhibit the maximum bent position throughout the cycle, with the thighs and knees almost lifted to the highest position. For example, the left thigh is raised approximately 37 degrees, and the inner side of the left knee joint is approximately 67 degrees, as shown in the figure. The degree of thigh elevation and knee flexion may be somewhat challenging for individuals with lower physical fitness levels or restricted leg mobility. Additionally, depending on the user's body size, the raised thighs may press against the abdomen, causing discomfort.

U.S. Pat. No. 7,713,176 discloses an exercise apparatus that allows users to perform leg exercises in a seated position. The equipment is equipped with the two pedals in front of the seat, and each pedal is connected to the front frame via a parallel four-bar linkage mechanism, allowing for a nearly linear reciprocating motion along a predetermined track, with the pedal angle remaining constant, oriented upward and backward for the user to pedal. Furthermore, the two pedals are interconnected and move in opposite directions. When one pedal descends forward and downward, the other pedal rises backward and upward. With this design, users can engage in alternating leg exercises and control the depth of each pedal press and the height of the lift without requiring the user to forcefully lift the thighs or flex the knees. However, when one pedal rises lower, the other pedal also descends proportionally, directly shortening the exercise range, which may lead to insufficient leg movement. Additionally, the user's legs repetitively extend forward and flex backward, similar to pedaling on a traditional bicycle, where the feet and knees always rise and descend together, resulting in a relatively monotonous motion.

Several exercise equipment option on the market enable similar pedaling exercises in a seated position. However, many of these devices have their mechanical components extending between the seat's underside and the front, such as a crank assembly positioned under the seat and the two connecting rods connecting the crank assembly to the two pedals in front of the seat. This design requires users to cross the connecting rods when preparing for exercise by sitting on the seat and when finishing the exercise and leaving the seat. This can be inconvenient and poses a risk of tripping over the connecting rods.

The present invention aims to address the issues of the prior art mentioned above. The main objective is to provide a recumbent exercise apparatus that allows a user to perform leg exercises in a seated position. During these leg exercises, the user performs a relatively gentle thigh elevation and degree of knee flexion while also providing sufficient foot movement range and leg activity. This design combines low exercise difficulty with high exercise effectiveness.

Another objective of the present invention is to provide a recumbent exercise apparatus that allows users to perform leg exercises in a seated position. During these leg exercises, the user's leg movements are natural and smooth, distinct from the monotonous repetitive extension, flexion, and the simultaneous elevation and descent of the feet and knees found in prior art.

Another objective of the present invention is to provide a recumbent exercise apparatus that allows users to perform leg exercises in a seated position. The structure of the movement mechanism is compact, and when users are getting ready for exercise, sitting on the seat, and finishing the exercise to leave the seat, there is no need to cross any components of the movement mechanism, making it more convenient and safe.

Another objective of the present invention is to provide a recumbent exercise apparatus that allows users to perform leg exercises in a seated position. Simultaneously, the users can choose to engage in coordinated hand movements during the leg exercises, enhancing the overall effectiveness of the workout.

In order to achieve the above objectives, the present invention provides a recumbent exercise apparatus that allows a user to perform a leg exercises in a seated position. The apparatus comprises a frame; a seat disposed on the frame to support the user in a fixed position; and a movement mechanism movably arranged on the frame and has a left pedal and a right pedal located in front of the seat for the user to step on with both feet respectively. Each pedal having a toe end, a heel end, and a middle portion located between the toe end and the heel end. When performing the leg exercise, the middle portion of each pedal cyclically displaces relative to the frame along a predetermined pedal exercise path based on the guidance of the movement mechanism. Additionally, an elevation angle between the toe end and the heel end cyclically changes in a predetermined manner. The predetermined pedal exercise path is located on a vertical plane defined by a vertical and longitudinal directions of the frame, having a highest position, a lowest position, a frontmost position, a rearmost position, a maximum elevation position and a minimum elevation position. The maximum elevation position is located within a path from the highest position to the lowest position while passing through the frontmost position, and the minimum elevation position is located within a path from the lowest position to the highest position while passing through the rearmost position. Wherein the toe end of each pedal remains higher than the heel end; during the middle portion moving from the maximum elevation position to the minimum elevation position along the predetermined pedal exercise path, the elevation angle of the toe end relative to the heel end decreases gradually. In addition, during the middle portion moving from the minimum elevation position to the maximum elevation position along the predetermined pedal exercise path, the elevation angle of the toe end relative to the heel end increases gradually.

Preferably, the distance of the predetermined pedal exercise path from the rearmost position to the highest position is greater than the distance from the highest position to the frontmost position.

Preferably, the height difference between the highest and the lowest positions of the predetermined pedal exercise path in the vertical direction is smaller than the difference between the frontmost and the rearmost positions in the longitudinal direction, and the predetermined pedal exercise path has a major axis with a relatively higher front end and a relatively lower rear end.

Preferably, the distance between the maximum elevation position and the frontmost position of the predetermined pedal exercise path is smaller than the distance between the maximum elevation position and the highest position, as well as smaller than the distance between the maximum elevation position and the lowest position. Similarly, the distance between the minimum elevation position and the rearmost position of the predetermined pedal exercise path is smaller than the distance between the minimum elevation position and the highest position, as well as smaller than the distance between the minimum elevation position and the lowest position.

Preferably, the maximum elevation position of the predetermined pedal exercise path is located between the frontmost position and the lowest position, and the minimum elevation position is located between the rearmost position and the highest position.

Preferably, the movement mechanism includes a left first connecting rod, a right first connecting rod, a left second connecting rod and a right second connecting rod, all positioned in front of the seat. Each first connecting rod comprises a surrounding portion, a first reciprocating portion and a first pivoting portion. The surrounding portion is restricted to moving along a circular path relative to the frame. The first reciprocating portion is restricted to moving along a first reciprocating path relative to the frame. Each second connecting rod comprises a second reciprocating portion and a second pivoting portion. The second reciprocating portion is restricted to moving along a second reciprocating path relative to the frame, and the second pivoting portion is pivotally connected to the first pivoting portion of the corresponding first connecting rod. When the surrounding portions of the first connecting rods rotate one circle along the circular path, the first reciprocating portions of the first connecting rods and the second reciprocating portions of the second connecting rods reciprocate once along the first reciprocating path and the second reciprocating path respectively. Additionally, the first pivoting portions of the first connecting rods and the second pivoting portions of the second connecting rods rotate one circle along a closed path. The change in a relative angle of the two ends of each second connecting rod is smaller than that of the two ends of each first connecting rod; the left and right pedals are respectively mounted on the left and right second connecting rods.

Preferably, each first connecting rod has a front end and a rear end, the surrounding portion is located at the front end, the first pivoting portion is located at the rear end, and the first reciprocating portion is located between the front end and the rear end. Each second connecting rod has a front end and a rear end, the second reciprocating portion is located at the front end, and the second pivoting portion is located behind the second reciprocating portion; and each pedal is positioned on a rear half of the corresponding second connecting rod.

Preferably, the first reciprocating path has a relatively higher front end and a relatively lower rear end; the closed path has a major axis with a relatively higher front end and a relatively lower rear end; the second reciprocating portion of each the second connecting rod is located higher than the second pivoting portion. In addition, wherein the second reciprocating path has a relatively higher front end and a relatively lower rear end. In a side view, the first reciprocating path intersects with an enclosed range of at least one of circular path and the closed path, and similarly, the second reciprocating path intersects with an enclosed range of at least one of the circular path and the closed path.

Preferably, the movement mechanism includes a left crank arm, a right crank arm, a left first swing arm, a right first swing arm, a left second swing arm and a right second swing arm, all positioned in front of the seat; each crank arm has an inner end and an outer end. The inner ends of the left and right crank arms are pivotally connected to the frame according to a first axis. The outer ends of the left and right crank arms are 180 degrees opposite to each other with the first axis as a center, and are respectively pivoted to the surrounding portion of the left and right first connecting rods. Each first swing arm has an axis end and a swing end. The axis ends of the left and right first swing arms are respectively pivoted to the frame according to a second axis. The swing ends of the left and right first swing arms are respectively pivoted to the first reciprocating portions of the left and right first connecting rods. Similarly, each second swing arm has an axis end and a swing end. The axis ends of the left and right second swing arms are respectively pivoted to the frame according to the second axis. The swing ends of the left and right second swing arms are respectively pivoted to the second reciprocating portions of the left and right second connecting rods. Both the first axis and the second axis correspond to a lateral direction of the frame.

Preferably, the movement mechanism includes a left lever and a right lever, the left and right levers are respectively connected to the left and right first swing arms or respectively connected to the left and right second swing arms. Each lever has a handle for the user to grasp; the swing end of each first swing arm and the swing end of each second swing arm are both lower than the second axis, and each handle is higher than the second axis.

The directional references, such as front, back, left, right, up, and down, provided in the following explanations are generally based on the user's directional perception when using the exercise apparatus of the present invention in a normal manner. For instance, front and back correspond to the direction the user is facing and the opposite direction respectively, during exercise. Left and right correspond to the user's left and right sides during exercise. The definitions of the longitudinal (front-back axial) direction, lateral (left-right axial) direction, and vertical (the up-down axial) direction of the exercise apparatus remain consistent based on the principles outlined above.

Referring toto. In a preferred embodiment of the present invention, a recumbent exercise apparatus that allows a user to perform specific leg exercises (and optional hand exercises) in a seated position. The exercise apparatus comprises a frame, a seat assemblylocated at the rear of the frame, and a movement mechanismlocated at a front portion of the frame.

The framecan be stably rested on a horizontal support surface (e.g., the ground) to serve as the installation foundation for components such as the seat assemblyand the movement mechanism. It comprises a basethat can be flatly placed on the support surface, a bracketfixed to the front half of the base, and a pillarextending upward and backward from the top of the bracket. The top of the pillaris equipped with a console. In this embodiment, the rear portion of the baseforms the rear part of the frame, while the remaining part forms the front portion of the frame, including the bracketand the pillar.

The seat assemblycomprises a sliding seatpositioned at the rear half of the base, a lift seatplaced on the sliding seat, a seatpositioned at the top of the lift seat, a chair backlocated behind and above the seat, a left handleand a right handleprovided on both sides of the seat, respectively. The sliding seatcan horizontally slide along the longitudinal axis on the rear half of the base, and allowing it to be located at a selected position within an adjustable range. Similarly, the lift seatcan vertically slide along the vertical axis on the sliding seatand be located at a selected position within an adjustable range. The seatallows the user to sit facing forward, supporting the user in a fixed position for leg exercises. The user can adjust the horizontal and vertical positions of the seataccording to their personal conditions. The chair backprovides back support for the user sitting on the seat, and the user can adjust the angle of the chair backbase on their personal preferences. The left and right handles, fixed relative to the seat, provide grip for the user's hands during leg exercises, aiding to stabilize the body and facilitate leg exertion. When the user is preparing to sit on the seator getting up from the seat, as shown inand, the seat(along with the chair backand handles) can be horizontally rotated by 90 degrees according to personal needs. This allows the user, especially the elderly, those with larger body sizes, or limited mobility, to sit or stand on the left or right side of the exercise apparatus, providing greater convenience. Additionally, when necessary, the seat assemblycan be moved backward to detach from the base, allowing wheelchair users to enter the corresponding area from the rear. After locking the wheels of the wheelchair, the users can directly sit on the wheelchair to engage in leg exercises (and hand exercises). The aforementioned functions of the seat assemblyare known in the prior art. For example, products like “StepOne™ Recumbent Stepper” produced by the American company SCIFIT (one of the products corresponding to U.S. Pat. No. 7,713,176) have similar functionalities. Therefore, detailed explanations of its specific structure and operation are omitted

The movement mechanismis movably mounted at the front portion of the frame, including a crank assembly, a left first connecting rod, a right first connecting rod, a left second connecting rod, a right second connecting rod, a left first swing arm, a right first swing arm, a left second swing arm, a right second swing arm, a left lever, a right lever, a left pedaland a right pedal. The overall structure is symmetrically arranged, with the left and right parts respectively located on the left and right sides of the frame, corresponding to the left and right sides of the user's body midline when sitting on the seat. Unless the seat assemblyis excessively moved forward, all components of the movement mechanismare positioned in front of the seatduring normal use. Therefore, when the user enters or exits between the movement mechanismand the seatbefore or after exercise (including rotating the seathorizontally by 90 degrees), there is no need to cross over any components of the movement mechanism, which makes it more convenient and safe.

The crank assemblyincludes a crankshaft, a left crank armand a right crank arm. The crankshaftis pivotally mounted at a predetermined position near the top of the frame, allowing it to rotate in place. Its axis (referred to as the first axis) Acorresponds to a lateral direction, and its left and right ends extend from the left and right sides of the framerespectively. Each crank armhas an inner end and an outer end. The inner ends of the left and right crank armsare fixedly connected to respective the left and right ends of the crankshaft, being pivotally connected to the frameaccording to the first axis A. This arrangement enables the outer ends of each crank armto displace along a circular path Taround the first axis Arelative to the frame(refer to). Additionally, the outer ends of the two crank armsare positioned 180 degrees opposite to each other with the first axis Aas a center. This configuration ensures that when one moves upward and forward, the other one moves downward and backward at the same angular velocity, and so on.

Each first connecting rodhas a front end and a rear end, with a pair of protrusionslocated between the front end and the rear end. The front end of each first connecting rodis pivotally connected to the outer end of the corresponding crank armthrough a pivot axiscorresponding to the lateral direction. This arrangement forms a surrounding portion at the front end of each first connecting rod, restricting its displacement relative to the frameto the circular path T. In this embodiment, the connection structure between the first connecting rodand the crank armis similar to a universal joint, designed to absorb geometric tolerances such as parallelism between them.

Each second connecting rodhas a front end and a rear end, and positioned on the inner side of a rear half of the second connecting rod, a support plateis fixedly connected (refer to). A side plateextends downward from the left and right sides of the support plate, with the bottom ends of the two side platescan be respectively positioned at the left and right sides of the rear end of the corresponding first connecting rod, completing the pivot connection through a pivot axiscorresponding to the lateral direction. In this embodiment, the rear end of each first connecting rodforms a first pivoting portion, and the bottom end of the side platesof each second connecting rodforms a second pivoting portion. The first pivoting portion and the second pivoting portion move in synchrony.

Each first swing armhas an axis end (top end in this embodiment) and a swing end (bottom end in this embodiment). The axis end is equipped with a shaft sleeveand is pivoted at a predetermined position near the top of the pillarbased on a second axis Acorresponding to the lateral direction, allowing the swing end to reciprocate. Similarly, each second swing armhas an axis end (top end in this embodiment) and a swing end (bottom end in this embodiment). The axis end is equipped with a shaft sleeveand is pivoted at a predetermined position near the top of the pillarbased on the second axis A, allowing the swing end to reciprocate. In this embodiment, as part of the front portion of the frame, a hangeris fixedly connected to a position near the top of the pillar. Additionally, a shaft rodhorizontally passes through and is fixedly connected to the hanger, as shown in. The axis of the shaft rodcorresponds to the second axis A. The shaft sleevesof the left and right first swing armscan be separately pivotally mounted on the left and right halves of the shaft rodthrough a bearing (not labeled in the figure) and are positioned relatively close to the hanger. Similarly, the shaft sleevesof the left and right second swing armsare separately pivotally mounted on the left and right halves of the shaft rodthrough a bearing (not labeled in the figure) and are positioned relatively away from the hanger. Additionally, the shaft sleevesof the second swing armsare positioned on the outside of the shaft sleevesof the first swing armsin parallel. The swing end of each first swing armis pivotally connected to the top of the protrusionsof the corresponding first connecting rodthrough a pivot axiscorresponding to the lateral direction. The swing end of each second swing armis pivotally connected to the front end of the corresponding second connecting rodthrough a pivot axiscorresponding to the lateral direction. The length of the first swing arm(defined as the perpendicular distance from the axis-end pivot axis to the swing-end pivot axis) is not equal to the length of the second swing arm(defined as before). In this embodiment, the swing radius of the first swing armis greater than the swing radius of the second swing arm.

The left and right leversare respectively connected to the left and right second swing arms, causing the left leverto pivot synchronously around the second axis Awith the left second swing arm, and the right leverto pivot synchronously around the second axis Awith the right second swing arm. In this embodiment, each leverhas a top end and a bottom end, with the bottom end being fixedly connected to the axis end (top end) of the corresponding second swing arm, specifically connected on the outer side of the shaft sleeve. The upper half portion of each leverforms a handlethat allows the user grip and swing back and forth. When the swing end (bottom end) of one side's second swing armswings forward, the corresponding handleon the same side will swing backward accordingly. Conversely, when the swing end swings backward, the handlewill swing forward. In another possible embodiment of the present invention (not illustrated), the left and right levers are respectively connected to the left and right first swing arms.

The left and right pedalsare respectively mounted on the left and right second connecting rods, specifically fixedly connected above the support plateon the inner side of the rear half of the second connecting rod. They are located relative to and between the bottom and front of the seat, providing for the user sitting on the seatto step on with both feet. As shown inand, each pedalhas a toe endpositioned closer to the front of the pedal, a heel endat the rear, and a middle portionlocated between the toe endand the heel end.

The components of the movement mechanismare interlinked, and the movement of any component causes corresponding movements in other components. Refer toand(Note: For clarity, only the left half of the movement mechanismis shown in the figures due to overlapping movement path of corresponding components in the left and right side views. For example, the outer end of the right crank armalso displaces along the circular path Tin the figure). Through the interconnected relationships of the components in the movement mechanism, along with the predefined dimensions and spatial positions of the components, as the front end (surrounding portion) of the first connecting rodrotates one full circle along the circular path T. The portion where the top of the protrusionof the first connecting rodis pivotally connected to the swing end of the first swing armreciprocates along an arc-shaped first reciprocating path Tonce. Simultaneously, the portion (pivot axis) where the rear end (first pivoting portion) of the first connecting rodis pivotally connected to the bottom end (second pivoting portion) of the side plateof the second connecting rodrotates along a closed path Tfor one revolution. At the same time, the portion (pivot axis) where the front end of the second connecting rodis pivotally connected to the swing end of the second swing armreciprocates along an arc-shaped second reciprocating path Tonce. Meanwhile, the handle, synchronously moving with the second connecting rod, reciprocates along an arc-shaped handle movement path Tonce. Throughout this process, the relative change in angle between the front and rear ends of the first connecting rodis approximately 50 degrees (Note: In one cycle, the maximum inclination angle of the front end of the first connecting rodrelative to the rear end is about 60 degrees, and the minimum is about 10 degrees). The relative change in angle between the front and rear ends of the second connecting rodis approximately 30 degrees, which is smaller than the angle change of the first connecting rod. In this embodiment, the top ends of the protrusionsof each first connecting rodform a first reciprocating portion, restricted to displacement along the first reciprocating path Trelative to the frame. The front ends of each second connecting rodform a second reciprocating portion, restricted to displacement along the second reciprocating path Trelative to the frame.

In this way, as the respective portions of the first connecting rodand the second connecting rodcyclically displace or reciprocate along their respective trajectories, the middle portionof the pedalcyclically displaces relative to the framealong a predetermined pedal exercise path T. Moreover, an elevation angle between the toe endand the heel endcyclically changes in a predetermined manner (detailed explanation follows). In this embodiment, the exercise apparatus is designed to allow users with an active movement way to engage in the leg exercises for fitness. Specifically, the user must exert appropriate force while stepping on the left and right pedalsto drive them cyclically along the predetermined pedal exercise path T, causing the crank assemblyto rotate through the motion of the first connecting rod. In this embodiment, as the crank assemblyrotates, a flywheelcan spin faster in place through a belt transmission mechanism. Additionally, there is a resistance devicepositioned near the flywheel, which can apply resistance to the flywheel, such as an eddy current brake. The user can adjust the resistance on the flywheelusing the resistance devicethrough the console, thereby modifying the effort required for displacing the pedals. Depending on the user's implementation choice, the crank assemblycan drive the flywheelto rotate in the same direction during both forward rotation (corresponding to clockwise rotation in) and reverse rotation (corresponding to counterclockwise rotation in). This means that the user will experience inertia and resistance when driving the pedalsin either the forward or reverse direction. Alternatively, by installing a one-way bearing between the crankshaftand the belt transmission mechanism, the flywheelwill not be driven when the crank assemblyrotates in reverse. In this case, the user only needs to overcome the rotational resistance of the flywheelwhen driving the pedalsin the forward direction and can freely decelerate and stop as desired.

In another possible embodiment of the present invention, the exercise apparatus is designed to allow users with a passive movement way to engage in the leg exercises for rehabilitation. In other words, the user's legs, positioned on the left and right pedals, can be automatically moved cyclically along the predetermined pedal exercise path Tby the pedals. This movement induces passive ROM exercises, including knee and hip joint movements. In a specific implementation, a motor can be used to replace the flywheel. The output torque of the motor, reversed by the belt transmission mechanism, drives the crank assemblyto rotate at a slower speed, thereby displacing the pedalsalong the predetermined pedal exercise path Tin a cyclic manner. In another possible embodiment of the present invention, the exercise apparatus can be used for performing the leg exercises in either an active or passive mode. Wherein, each of the pedalmay be equipped with straps for appropriately restraining the user's feet.

The first axis Aand the second axis Abetween the movement mechanismand the framecorrespond to the lateral direction of the frame. Therefore, the circular path T, the first reciprocating path T, the closed path T, the second reciprocating path T, the handle movement path T, and the predetermined pedal exercise path Tare all located on a vertical plane defined by a vertical and longitudinal directions of the frame. In other words, various parts of the movement mechanismonly undergo vertical and longitudinal displacements, without any lateral movement. As shown in, the predetermined pedal exercise path Tis somewhat oval-shaped, and having a highest position P, a lowest position P, a frontmost position P, and a rearmost position P. In this embodiment, the height difference between the highest position Pand the lowest position Palong the vertical axis is approximately 17 centimeters, while the front-back difference between the frontmost position Pand the rearmost position Palong the horizontal axis is approximately 30 centimeters. The height difference is smaller than the front-back difference. Additionally, the predetermined pedal exercise path Thas a major axis L (Note: the major axis is defined as the direction connecting the two points farthest apart on the closed path), with the major axis L having a front end (left end in Figure) and a rear end (right end in Figure). While the front end is higher than the rear end, but the relative elevation is smaller than 45 degrees, approximately 14 degrees in this embodiment. In addition, the distance (P-P) of the predetermined pedal exercise path Tfrom the rearmost position Pto the highest position Pis greater than the distance (P-P) from the highest position Pto the frontmost position P. The distance (P-P) of the predetermined pedal exercise path Tfrom the frontmost position Pto the rearward and downward to lowest position Pis greater than the distance (P-P) from the lowest position Prearward and upward to the rearmost position P.

Since the left and right pedalsare respectively mounted on the left and right second connecting rods, when the middle portionof each pedalcyclically moving along the predetermined pedal exercise path T, a relative angle between its front and rear ends will be continuously changed along with the corresponding second connecting rod. The toe endof each pedalis always higher than the heel end. Additionally, as shown in, during one complete cycle of rotation of the middle portionof the pedalalong the predetermined pedal exercise path T, the elevation of the toe endrelative to the heel endgradually increases and then decreases. In particular, the predetermined pedal exercise path Thas a maximum elevation position Pand a minimum elevation position P. The maximum elevation position Pis located within the path from the highest position Pto the lowest position Pwhile passing through the frontmost position P, and the minimum elevation position Pis located within the path from the lowest position Pto the highest position Pwhile passing through the rearmost position P. When the middle portionof the pedalis located at the maximum elevation position P, an elevation angle of the toe endrelative to the heel end, termed as the maximum elevation angle, is within the range of greater than 30 degrees and smaller than 60 degrees, approximately 48 degrees in this embodiment. Conversely, when the middle portionof the pedalis located at the minimum elevation position P, the elevation angle of the toe endrelative to the heel end, termed as the minimum elevation angle, is within the range of greater than 0 degrees and smaller than 30 degrees, approximately 18 degrees in this embodiment. The angular difference between the maximum and minimum elevation angles is greater than 15 degrees and smaller than 45 degrees, approximately 30 degrees in this embodiment, equal to the angular variation of the second connecting rodrelative to the frame. Imaginatively, during the process in which the middle portionmoving from the maximum elevation position Pto the minimum elevation position Palong the predetermined pedal exercise path T, the elevation angle of the toe endrelative to the heel enddecreases gradually. In the preceding process, as the middle portionmoving from the minimum elevation position Pto the maximum elevation position Palong the predetermined pedal exercise path T, the elevation angle of the toe endrelative to the heel endincreases gradually. As a side note, the elevation angle of the toe endrelative to the heel endwhen the pedalis located at the highest position Pis approximately 36 degrees, at the frontmost position Pis approximately 47 degrees, at the lowest position Pis approximately 36 degrees, and at the rearmost position Pis approximately 19 degrees.

Preferably, the distance between the maximum elevation position Pand the frontmost position Pis smaller than the distance between the maximum elevation position Pand the highest position P, and also smaller than the distance between the maximum elevation position Pand the lowest position P. In essence, the maximum elevation position Pis relatively closer to the frontmost position Pand relatively farther from the highest position Pand the lowest position P. Additionally, the distance between the minimum elevation position Pand the rearmost position Pis smaller than the distance between the minimum elevation position Pand the highest position P, and also smaller than the distance between the minimum elevation position Pand the lowest position P. In essence, the minimum elevation position Pis relatively closer to the rearmost position Pand relatively farther from the highest position Pand the lowest position P. In this embodiment, the maximum elevation position Pis located between the frontmost position Pand P, and the minimum elevation position Pis located between the rearmost position Pand the highest position P. Moreover, the path from the minimum elevation position Pto the forward and upward direction towards the highest position Papproximately forms a straight line.

Due to the continuous change in a relative angle of the front and rear ends of the pedalduring cyclically displaces, the movement path of the toe endand the heel endare distinct. As shown in, the toe endcyclically displaces along a relatively elongated outline, represented by the toe movement path T, relative to the frame. In contrast, the heel endcyclically displaces along a relatively rounded outline, represented by the heel movement path T, relative to the frame. The difference in shapes between the toe movement path Tand the heel movement path Treflects the gradual reduction of the pedal's elevation angle from the maximum elevation position Pto the minimum elevation position Pand the gradual increase from the minimum elevation position Pto the previously mentioned maximum elevation position P. Similar to the predetermined movement path T, the front-back difference of the toe movement path Tand the heel movement path Tis greater than the up-down difference. Furthermore, the distance from the rearmost position to the highest position is greater than the distance from the highest position to the frontmost position.

Please refer toagain. In order to generate the predetermined pedal exercise path Tor a similar shape as shown in the figure, and the variation pattern of the pedal elevation angle, in this embodiment, the first reciprocating portion of the first connecting rod(i.e., the top of the protrusion) is located between the surrounding portion (front end) and the first pivoting portion (rear end). Additionally, the first reciprocating path Tis relatively located behind and below the center of the circular path T, having a relatively higher front end and a relatively lower rear end. This configuration resulting in the closed path Thaving a major axis (defined as before) with a relatively higher front end and a relatively lower rear end. Simultaneously, the second reciprocating portion of the second connecting rod(front end) is located forward and upward of the first and second pivoting portions, and the second reciprocating path Talso has a relatively higher front end and a relatively lower rear end. Furthermore, in this embodiment, the swinging ends (bottom ends) of the first swing armand the second swing arm, which share the same axis but have different lengths, respectively guide the first reciprocating portions of the first connecting rodsand the second reciprocating portions of the second connecting rods. In a side view, the first reciprocating path Tintersects with an enclosed range of at least of the circular path Tand the closed path T(in this embodiment, the latter). Similarly, the second reciprocating path Tintersects with an enclosed range of at least of the circular path Tand the closed path T(in this embodiment, the former). Through this mechanism, the movement mechanismcan provide a larger or sufficient pedal path in a smaller space with a more compact structure. In another possible embodiment of the present invention (not shown), the first reciprocating portions of the first connecting rods and/or the second reciprocating portions of the second connecting rods are equipped with rollers. These rollers can reciprocate along preset guide rails on the frame, also restricted to displace on a first reciprocating path and/or a second reciprocating path. Through this structure, similar exercise paths and elevation angle variations can be achieved.

The following describes the actions and effects of users utilizing the exercise apparatus in this preferred embodiment for leg exercises (and arm exercise). As shown in, during the exercise, the user is seated facing forward on the seat(Note: the seatin the figure is positioned for the comfort and suitability of the user; if the seatis in an inappropriate position, the user may not be able to perform the following actions correctly and comfortably). The left foot and right foot are placed on the left and right pedals, respectively, while the left hand and right hand typically grip the left and right handles, respectively. Both legs and hands coordinate to apply force, driving the respective pedalsand handlesto cyclically displace along the predetermined pedal exercise path Tand reciprocate along the handle exercise path T. Based on the interconnection of components in the movement mechanism, in general, when the left pedalmoves forward, the left handlemoves backward; simultaneously, the right pedalmoves backward, and the right handlemoves forward. This is similar to the balance of limbs when a person walks or runs. However, the user can also choose to grip the handleson both sides of the seatseparately, performing only leg exercises. In another possible embodiment of the present invention (not shown), the exercise apparatus does not provide the functionality for arm exercises. For example, by removing the leversand placing fixed handles near the corresponding positions.

In general, the user apply force to drive each pedalalong the predetermined pedal exercise path Tin the positive direction. That is, the pedalsdisplace from the highest position Pthrough the frontmost position Pto the lowest position P, and then from the lowest position Pthrough the rearmost position Pback to the highest position P, repeating this cycle. Of course, the user may also apply force to drive each pedalin the opposite direction. The sequence of(and then back to) corresponds to the process of positive displacement. In, the left pedalis located at the minimum elevation position Pon the predetermined pedal exercise path T. Conversely, in, the left pedalis located at the maximum elevation position Pon the pedal exercise path T. In other words, the left pedalundergoes the process from the position shown in, along the predetermined pedal exercise path Tthrough the positions shown in, to reach the position shown in. During this process, the elevation angle of the toe end of the pedalrelative to the heel end increases gradually. Conversely, the left pedalundergoes the process from the position shown in, along the predetermined pedal exercise path Tthrough the position shown in, to return to the position shown in. During this process, the elevation angle of the toe end of the pedalrelative to the heel end decreases gradually.

In coordination with the user's leg movements, in a general or typical usage state, when the user's left foot is flat on the left pedalpositioned at the minimum elevation position P, the left thigh is usually slightly elevated (elevation angle approximately 12 degrees in), and there is usually an acute angle between the left lower leg and the left thigh (approximately 80 degrees in). When the user's left foot is flat on the left pedalpositioned at the highest position P, the angle between the left lower leg and the left thigh is typically obtuse (approximately 120 degrees in). During the process of the user's left foot moving from the minimum elevation position Pto the forward and upward to reach the highest position P, it passes through a specific position as shown in. At this point, the user's left thigh and left knee are raised to the highest height throughout the movement (elevation angle approximately 15 degrees in), and there is generally a right angle between the left lower leg and the left thigh. It is worth noting that during the stage fromto, the user's left thigh and left knee begin to gradually lower, but the left foot continues to displace forward and upward with the left pedal, causing the left lower leg to swing upward relative to the left knee. After passing the highest position, the left pedalcontinues to move away from the seat, meaning that the user's left foot continues to move away from the seat. Therefore, the user's left leg continues to stretch, and the elevation angle of the left foot continues to increase until the left pedalreaches the maximum elevation position P. At this position, the user's left leg is close to fully extended, and the left thigh and left knee are lowered to the lowest height throughout the movement (angle of depression approximately 12 degrees in). Subsequently, the user's left leg begins to bend, the left thigh and left knee start to rise, and the elevation angle of the left foot gradually decreases until the left pedalreturns to the minimum elevation position Palong the predetermined pedal exercise path T, repeating this process continuously. Even if the user's hands do not push or pull the handle, because the left and right pedalsgenerally remain their relative positions on the predetermined pedal exercise path T, there is always at least one side that can be driven by the user's force at applied any time. Coupled with the motion inertia provided by the flywheel, each pedalcan rotate smoothly and continuously. The leg movements are also applicable for the passive movement.

The above-mentioned exercise apparatus of the present invention has at least the following advantages or features:

1. During these leg exercises, the user performs a relatively gentle thigh elevation and degree of knee flexion while also providing sufficient foot movement range and leg activity. This design combines low exercise difficulty with high exercise effectiveness.

2. During these leg exercises, the user's leg movements are natural and smooth, distinct from the monotonous repetitive extension, flexion, and the simultaneous elevation and descent of the feet and knees found in prior art.

3. The structure of the movement mechanism is compact, and when users are getting ready for exercise, sitting on the seat, and finishing the exercise to leave the seat, there is no need to cross any components of the movement mechanism, making it more convenient and safe.

4. The users can choose to engage in coordinated hand movements during the leg exercises, enhancing the overall exercise effectiveness of the workout.